Specimen Design and Construction

Design

 The manufacturing of circular shape piles using traditional precast methods is

difficult. In order to produce a circular shape a closed form mold is necessary. Casting

concrete inside a circular closed form mold presents a significant challenge since it is

necessary to pump the concrete though openings and then compact it though vibration or

other means. These challenges make manufacturing difficult and time consuming which

results in higher costs that make these poles/piles economically unfeasible. That is

probably why such a method to produced circular shape poles/piles has not been

employed by the concrete pole/pile industry.

 On the other hand, the spun-cast method used to produce prestressed concrete

poles/piles provides a viable option to produce a circular cross-section. This method has

been used successfully for more than two decades. Some of the advantages associated

with the spun-cast method are:

* Spun-cast piles can be produced in a number of sizes and lengths.

* The piles are produced in a circular shape which is the most effective shape for
 confinement.

* Vibration of the concrete is not necessary.

* The concrete is highly compacted due to the spinning process. That produces high
 density concrete piles with low permeability which for the same cover provides
 improved environmental protection.

* The equipment and expertise are already available and can be used to produce FRP
 reinforced spun-cast piles.

 The drawbacks of the spun cast method are the following:

* The circular shapes produced by the spun-cast method are tapered which results in
 piles with different sectional properties along their length.